Fig. 1 General VirScan analysis of the human virome. General VirScan analysis of the human virome. (A) Construction of the virome peptide library and VirScan screening procedure. (a) The virome peptide library consists of 93,904 56–amino acid peptides tiling, with 28–amino acid overlap, across the proteomes of all known human viruses. (b) The 200-nt DNA sequences encoding the peptides were printed on a releasable DNA microarray. (c) The released DNA was amplified and cloned into a T7 phage display vector and packaged into virus particles displaying the encoded peptide on its surface. (d) The library is mixed with a sample containing antibodies that bind to their cognate peptide antigen on the phage surface. (e) The antibodies are immobilized, and unbound phage are washed away. (f) Last, amplification of the bound DNA and high-throughput sequencing of the insert DNA from bound phage reveals peptides targeted by sample antibodies. Ab, antibody; IP, immunoprecipitation. (B) Antibody profile of randomly chosen group of donors to show typical assay results. Each row is a virus; each column is a sample. The label above each chart indicates whether the donors are over 10 years of age or at most 10 years of age. The color intensity of each cell indicates the number of peptides from the virus that were significantly enriched by antibodies in the sample. (C) Scatter plot of the number of unique enriched peptides (after applying maximum parsimony filtering) detected in each sample against the viral load in that sample. Data are shown for the HCV-positive and HIV-positive samples for which we were able to obtain viral load data. For the HIV-positive samples, red dots indicate samples from donors currently on highly active anti-retroviral therapy (HAART) at the time the sample was taken, whereas blue dots indicate different donors before undergoing therapy. IU, international units. (D) Overlap between enriched peptides detected by VirScan and human B cell epitopes from viruses in IEDB. The entire pink circle represents the 1392 groups of nonredundant IEDB epitopes that are also present in the VirScan library (out of 1559 clusters total). The overlap region represents the number of groups with an epitope that is also contained in an enriched peptide detected by VirScan. The purple-only region represents the number of nonredundant enriched peptides detected by VirScan that do not contain an IEDB epitope. Data are shown for peptides enriched in at least one (left) or at least two (right) samples. (E) Overlap between enriched peptides detected by VirScan and human B cell epitopes in IEDB from common human viruses. The regions represent the same values as in (D) except only epitopes corresponding to the indicated virus are considered, and only peptides from that virus that were enriched in at least two samples were considered. (F) Distribution of number of viruses detected in each sample. The histogram depicts the frequency of samples binned by the number of virus species detected by VirScan. The mean and median of the distribution are both about 10 virus species. George J. Xu et al. Science 2015;348:aaa0698 Copyright © 2015, American Association for the Advancement of Science